Tension responsive drive control mechanism



Sept. 27, 1960 R. FULGHUM 2,954,179

TENSION RESPONSI VE DRIVE CONTROL MECHANISM Filed Feb. 8, 1957 2Sheets-Sheet l INVENTOR. ROBERT L FULGHUM ATTORNEY Sept. 27, 1960 R.FULGHUM, 2,954,179

TENSION RESPONSIVE DRIVE CONTROL MECHANISM Filed Feb. 8, 1957 2Sheets-Sheet 2 C &

32 E 2 g g 30 36 ax INVENTOR. ROBERT L. FULGHUM a 6 82 BY 2 7 f L/ 5 ATTORNZIY United States Patent TENSION RESPONSIVE DRIVE CONTROL MECHANISMRobert L. Fulghurn, 184 Forsyth st. sw., Atlanta, Ga. Filed Feb. 8,1957, Ser. No. 638,996 2 Claims. '(Cl. 242-755 paper and textiles,material is frequently fed at a constant rate of speed by feed rollsoperating at a' uniform speed to be wound upon a receiving roll. Thereceiving roll winds the material in successive layers thereover. It isof course obvious that the effective diameter of the receiving rollincreases as the material builds up ',there- 1 on; hence, since the rateof feed is constant, should the receiving roll be rotated at a constantrate of speed the increased effective diameter thereof will provideincreasing tension on the material, frequently to the breaking pointThus in such devices it is customary to;provide :sor'ne compensatingmeans whereby the speed of rotation of the feeding roll will becommensurate with the increased radius of the material thereon so astoseekto establish a substantially uniform tension-on the materialbetween the feeding rolland the receiving roll. A wide 1 variety ofmechanisms have been developedand are in successful use by whichcompensation is introduced into the drive mechanism of the receivingroll soas to adjust the speed in accordance with the increasingeffective diameter as material is supplied thereto. Since an importantfactor is the maintenance ofa uniform tension on the material, suchcompensating devices-are frequent- 1y directly responsive to suchtension. 1 I 1 iModern equipment of thisitype is usually motivated by aconstant speed electric motor, and compensating detvices most frequentlyinvolve a continuously variable speed-change mechanism between thesourceof power and the receiving roll. One such continuously variable.transmission mechanism .is commonly known as the -Reeves drive whichincludes opposed cone pulleys, the effective diameters of which may bealtered while in op- .eration to provide a variation in the speedtransmitted therebetween. Tension responsive drive mechanisms have Jalsoemployed various types of hydraulic couplings ..wherein change of thetorque through the hydraulic -mechanism which may produce slippage mayberesponhsive to the tension applied between the feed rollerfand -thereceiving rollers, thus compensating forchanges in the effectivediameter of the receiving roll. Differential .dgive mechanisms have alsobeen employed as, for instance, .where theifeed roller is driven fromthe 'same xsourceof power as the receiving roller, since the speed ofrotation ultimately delivered to' the receiving -roller must of coursevary with respect to the speed'of rotaation'of the feed roller.

Whilemany of these prior art drive effective and efficient in securingan adjustment of the [speed of the receiving roll in accordance with theincreased effective diameter thereof as material is built upon thereceiving roll, they have not; allbeen ideal in devices have been,device of Fig. 1.

sensitive tension response, and for the most part such arrangements havebeen complicated, expensive and difficult of maintenance and adjustment.In the present arrangement, a fluid coupling is provided and thesensitive torque responsive slip thereof is utilized for the control ofa differential mechanism which in turn controls a speed change mechanismthrough which the winding roller is driven. Since the speed changemechanism is controlled by' the slippage of the fluid drive mechanism,and since such slippage is direct- 1y responsive to tension applied, itwill be seen that an ac curate and sensitive control under the influenceof the load of the roller is achieved. i

It is therefore among the primary objects of the present invention toprovide a drive mechanism for winding rolls and the like which includesmeans responsive to the change in effective diameter of such rolls bywhich the speed thereof may be adjusted in order to maintain a uniformwinding tension.

Another object of the present inventionis to provide in a device of thecharacter described the combination of a hydraulic transmission and adifferential, the cooperating elements of which are individually drivenfrom the positive drive of the hydraulic transmission and the slipdriven side of the hydraulic transmission in order to control a finalspeed output. 1 i

It is also amongthe objects of the present invention to provide awinding mechanism which is torque responsive in such manner as to vary aspeed-change mechanism in response to tension applied to materialbetween feed rolls and a winding roll. I p It is also an object of thepresent invention to provide in a drive of the character set forth atension responsive hydraulic coupling together with a differentialbetween the slip side of the coupling and the constant speed drivethereof, there being a speed-change mechanisrncontrolled by thedifferential.

Numerous other objects, features and advantage of the present inventionwill be apparent from consideration of the following specification takenin conjunction with the accompanying drawings, in which: 7 Fig. 1 is aside elevation of one form of the present invention.

Fig. 2 is a detail top plan view of the drive of the Fig. 3 is a detailenlarged cross-sectional view 'taken through the central shaft'of thedifferential of Fig: 2 taken on a plane parallel to the plane of the topplan view of Fig. 2. i

:Fig. 4 is a similar cross section taken through the auxiliary shafts ofthe differential. v '1 Referring more particularly to the drawings, itwill be seen that that form of the present invention here shown by wayof example includes a prime mover 10 preferably in the'form of aconventional alternating current constant speed electric motor. From theoutput shaft 11 of the motor 10, a V-beltdrive indicated at 12 rotatesthe constant speed positive drive shaft 13 of a torqueresponsivehydraulic coupling generally indicated at 14. The

hydraulic coupling here illustrated may be more accurately defined as ahydro-dynamic type fluid coupling wherein the torque delivered by theconversion of kinetic energy to dynamic energy'is, for all practicalpurposes,

proportionate to the relative rotating speed of the input and outputelements so long as the'input elementis 13 will drive the impeller 15 ofthe coupling 14'Wl1il6 'Ihustheshafts 13 and 18 will rotate at speedswhich the runner 16 of the coupling is mounted on the variable speedoutput shaft 18 within the rotating housing'17.

3 may vary through slippage in direct proportion to the torque requiredfrom the output shaft 18. To transmit torque there must always bepresent, in the fluid coupling, slip, and the amount of torquetransmitted through this coupling is dependent upon the amount of slipwithin the coupling, therefore, there will always be a differentialbetween the speed of rotation of shafts 13 and 18, and therefore,suitable ratios will be established in the drive 20 and the drive 36 toprovide the following described results.

The constant speed and positively driven shaft 13 is also provided witha V-belt drive 20 for the rotation of a shaft 21 coupled by gearing 22and 23 to the left hand central gear 24 of a differential which includesthe supporting rectangular housing or bracket 25. The opposedcounterpart central drive of the'dilferential driven by the variablespeed shaft 18, comprises sprocket30 and gear 31. A chain 32 driven fromshaft 33, which latter is in turn driven by V-belt 36 from the shaft 18of the main gear 31, provides the drive for this variable speed gearingof the differential.

It will, of course, be understood that the differential mechanism issuch that when the proper ratio is estab lished between shaft 13 andshaft 21, as well as a proper ratio between shaft 13 and shaft 33, indue consideration of the predetermined required amount of torque, andtherefore slip, to be transmitted through the fluid coupling, generallyindicated at 14, to the drive 64, the result will be that gears 24 and31 are driven at ,equal speeds and the housing 25 of the differentialwill be at rest; however, upon a differential in speed between theseshafts, the housing 25 will be revolved, in a clockwise, orcounterclockwise, direction depending upon whether the amount of torquecalled upon to be delivered by the fluid coupling is more or less thanthe predetermined amount. 7

This rotation of the housing 25 in response to speed variations isprovided for by the interrelated side gearing including a gear 40 onshaft 41 meshing with gear 24 in combination with gear 42, also on shaft41, meshing with a gear 43 on a parallel shaft 44 and a gear 45 on theshaft 44 meshing with the gear 31. It will be understood that the gears24 and 31 are of equal diameter and tooth number. The gears 40, and45are equal in diameter and tooth number, as are gears 42 and 43. Theshafts 41 and 44 are mounted through the end plates 46 of the housing 25and through the parallel intermediate plate 47 thereof. The gears 23 and24 are unitized for rotation together as by press fit, or thelike, on asleeve 48 (Fig. 3) as are the gear 31 and sprocket 30 on their sleeve49. Both sleeves are freely rotatable on the central differential shaft50 to which the housing is secured for rotation therewith as by aretaining pin 51. Since such differentials are well known in the art, itis believed that its operation will be fully understood. Suffice it,therefore, to point out that, when a change in speed between shafts 13and 18 takes place, the gears 40 and 45 with their shafts 41 and 44 willhave planetary motion about the gears 24 and 3 1, respectively, to turnthe housing 25 clockwise or counterclockwise in response to whichevershaft and gearing rotate faster. Such movement of the housing will be ata rate dependent upon the speed differential.

The shaft 50, to which the housing 25 is secured, carries an externalsprocket 52' rotatable therewith. A chain 53 trainedover sprocket 52 isalso trained over sprocket 54 of a speed control shaft 55 of aspeed-change mechanism generally indicated by the numeral'56. Thespeedchange mechanism of the type here shown includes pairs of opposeddrive and driven cones or pulleys 60 and 61, respectively, the relativeeffective diameters of which are adjusted by opposed arms 62 pivoted at63 and movable by the oppositely threaded portions of the speed controlshaft 55. Power is transmitted from the outlet or slip side of thehydraulic coupling 14 through shaft 18 to V- belting indicated at 64 todrive the shaft 65 mounting the pulley 60 of the variable speedtransmission. The output shaft 66 of the variable speed transmissiondrives a chain 67 associated by gearing 68 with a chain 69 for drivingthe take up roll 70. The constant speed feed rollers 80 may be driven inany desired manner. As here shown they are driven from the constantspeed shaft 13 by belting 81 and shaft 82.

In the operation of the illustrated form of the invention, when themotor 10 is energized its shaft 11 and hence the shaft 13 will be drivenat a constant speed which will not vary in response to variation in loadthroughout the apparatus. Shaft 21 will likewise be driven at a constantspeed, Since the gears 22, 23 and 24 of the differential mechanism aredriven with the constant speed shafts 21 and 13, it will be observedthat these gears will be rotated at a continuously constant speed. "Theshaft 18 of the slip or runner side of the hydraulic transmissioncoupling 14 is arranged through the V -belting 36 to drive thedifferential gearing 31. As aforesaid, should the speed of rotation ofgear 31 vary from that of gear 24, the differential housing 25 will berotated. Such rotation will alter the setting of the speed changemechanism. Thus it will be seen that the torque or resistance torotation of the roller will be reflected to the belting 64 to apply aresistance to the rotation of the hydraulic transmission as the torqueof the take-up roller varies. Hence, upon variation of such torque,there will be a variation in slippage in the hydraulic transmission, andsince the output of this hydraulic transmission is connected by theV-belt 36 to the opposite side of the differential it will be noted thatwhen such slippage occurs the gearing 3th to 31 of the differential willrotate at a speed different from the gearing 22 to 24, and hence thedifferential housing 25 will be rotated in consequence of, andproportionately to, difference in speed of rotation by the two sets ofgears of the differential. Such'rotation of the differential housingwill be imparted to the shaft 50 and chain 53 to the shaft 55 which willbe rotated to alter the speed responsive setting of the speed-changemechanism 56, such alterations continuing until such speed changecompensates for thechange of torque, at which time the speed delivery issuch as to restore the slippage'within the hydraulic coupling to thepredetermined figure, the differential gearing will then rotate at auniform speed and the housing will remain stationary until a furtherchange in torque is applied.

In this arrangement, it will also be noted that the feed rolls 80 aredriven through the V-belt 81 from the constant speed side of thehydraulic transmission; thus, there Will be a constant rate of feed atall times requiring a constant rate of take-up by the roll 55.

From the foregoing it will be seen that the present invention provides anovel, simple and improved construction and arrangement of parts wherebyuniform tension is applied to material passing from the feed roll to thetake up roller, and the invention further provides for the combined useof a hydraulic transmission which is sensitive to torque changes and bywhich such torque changes will operate the differential mechanism to provide for a change of take-up speed so as to maintain a uniform tensionon material passing between feed rollers and take up rollers. "It willof course be understood that in the practice of the invention numerouschanges, modifications and the full use of equivalents may be resortedto without departing from the spirit or scope of the invention asdefined in the appended claims.

I claim:'

1. In a tension responsive drive for take up-rolls the combination witha constant speed 'source of power, a hydro-dynamic type fluid couplingdriven by said source of power having a driven constant speed impellerside and a driving slip housing side, power take-off from the sliphousing side of said coupling fordriving a take up roll, speed changemechanism in said take-off between the slip housing side of saidcoupling and said roll, a difierential including a drive from theconstant speed source and a drive from the slip housing side of thecoupling, a housing rotatable in response to variations of speed betweenthe driven side of said coupling and the slip housing side of saidcoupling, a speed change shaft for said speed change mechanism rotatableby rotation of said housing, and a constant speed drive from saidconstant speed source of power to a feed roll for delivering material tothe take up roll.

2. The device as set forth in claim 1 in which the speed changemechanism includes a pair of opposed cones, the efiective diameters ofwhich may be varied by rotation of said speed change shaft and a powertransmitting belt therebetween.

References Cited in the file of this patent UNITED STATES PATENTS2,392,226 Butterworth et a1. Jan. 1, 1946 2,496,977 Bechle Feb. 7, 19502,658,692 Wolf Nov. 10, 1953 2,678,485 Browne May 18, 1954

